The present invention relates to a method and arrangement for setting an equalization characteristic of an amplitude equalizer for use in a modulating and demodulating device (hereinafter referred to as MODEM).
Generally, a MODEM includes an amplitude equalizer having a plurality of different amplitude equalization characteristics one of which is selected in matching relation to a particular communication line connected to the MODEM. It has been customary to select an optimum characteristic for a particular communication line by adopting one of two different approaches: first in the event of installation of a MODEM a technical expert connects a transmission characteristic measuring device or similar device to opposite ends of the line to which a MODEM is to be connected and thereby determines an optimum equalization characteristic for that line second, a person actually causes a MODEM to operate while observing the resulting eye pattern on an oscilloscope or the like and selects an equalization characteristic which makes the eye opening associated with the quality of transmission characteristic largest. Both of these prior art approaches share the problem or requiring an expert to be dispatched to the actual location of installation, and of requiring a special device for measurement.